Bugfix: Pretty URLs

When you save a page, ditzie attempts to convert a numeric reference to an image set into “pretty” format. Unfortunately, If you were using a non-top-level set, this would result in a “page not found” error when saving.

For example, you load up http://beta.ditzie.com/680, which takes you to the D&D maps folder (Beta >> dnd >> maps, if you were to navigate there via the gallery). You position a few items and hit return to save. Instead of redirecting you to http://beta.ditzie.com/680/NEWPAGEID, you get sent to http://beta.ditzie.com/dnd/maps/NEWPAGEID, which turns into a 404 (file not found) error.